Most Helpful Guy
Hey there! :o)
Ok, I was going to say something similar at first to what CrystalMinds said about trying to talk with this guy and explain to him how you feel about what he is doing. If you really like this guy, but his behavior in the way you describe is bothering you, then maybe this is something you can talk to him about and work on.
However, from reading your comments, I can see that you don't really love this guy and you seem pretty sure that you want to break up with him. If that is truly the case and you are absolutely sure that you want to break up with this guy and there is nothing left that you want to 'work on', then my advice to you is to break up with him as soon as possible!
How long have you been with this guy? Weeks? Months? A year or more? Unless this is a long term relationship where you have become emotionally close, then I see no harm in breaking up with him via text or other similar message. If you have been together a while and become close, then I would always say give this guy the respect of breaking up with him face-to-face. However, if this is relatively short-term, then unless you specifically want to break up with him face-to-face, then I feel you could simply message him. Do this as soon as possible, today if necessary, and just get it out of the way now that you know for sure what you want to do! Please don't string him along, or play stupid games that may or may not work... Just break up with him the right and decent way and apart from maybe some guilt, you'll feel a whole lot better later!
As for what to say, keep it short and sweet, but explain your reasons. Something like 'Hi NAME. I'm really sorry, but I just don't think this is working out for me. You're a real nice guy and I really appreciate all the effort you've put in for me, but I just don't feel the chemistry is right between us and you deserve someone who is able to reciprocate your efforts. I'm really sorry, but I think this is for the best and I know you can find someone more suitable. I'm sorry if I've upset you, but I really hope we can still be friends. YOUR NAME'. Something like that anyway.
If your decision is made and there's no way that you are going to change your mind, then either text or say something like that to him and get it over with, for the sake of both of you! It may be hard and no doubt you will have to deal with his questions, but just be nice and stick to you reasons (without being overly critical) and just make it clear that's the chemistry and relationship is not right for you!
I hope that helps you and please feel free to ask me any further questions... :o)